Question

For a given binomial distribution with  n = 11, p = 0.35, find the following probabilities P( x is less than or equal to 6, x≤ 6)

Answer 1

Solution:

We are given

n = 11

p = 0.35

q = 1 - 0.35 = 0.65

np = 11*0.35 = 3.85 < 5

So, we cannot use normal approximation.

We have to use binomial distribution.

We have to find P(X≤6)

P(X≤6) = 0.949857

[by using excel command =BINOMDIST(6,11,0.35,1)]

[You can also use Ti-84/83 calculator or other software for finding this probability. You can use binomial table for finding this probability, but you will get approximate probability by using table.]

Answer: P(X≤6) = 0.949857